Jet power plant with unobstructed rotating combustion chamber



June 3, 1958 J. A. WARD 111 2,836,958

JET POWER PLANT WITH UNOBSTRUCTED ROTATING'COMBUSTfON CHAMBER Filed Feb. 17, 1954 2 Sheets-Sheet 1 IN VENTOR ATTORNEY June 3, 1958 J. A. WARD 111 2,836,958

JET POWER PLANT WITH UNOBSTRUCTED ROTATING COMBUSTION CHAMBER Filed Feb. 17, 1954 2 Sheets-Sheet 2 INVENTOR Jo/m J4 Z0420, E

ATTORNEY Fatented June 3, 1958 JET POWER PLANT WITH UNOBSTRUCTED ROTATING (IGMBUSTION CHAMBER John A. Ward Hi, Duluth, Minn.

Application February 17, 1954, Serial No. 410,905

5 Claims. (Cl. 6039.35)

The invention relates to improvements in jet engines, and more particularly to an improved jet engine comprising a rotatably mounted engine unit including a front compressor portion, an unobstructed intermediate tubular body portion which includes the combustion chamber, and a rear turbine portion.

The invention is adapted for use in commercial and military airplanes, and its simplicity of design permits its use as well in miniature engines for toys or model airplanes.

In previous devices of this general character with which I am familiar the problem of supplying fuel to the combustion chamber has been a serious one. In prior patents various means of feeding fuel have been suggested which generally require some sort of rotating or flexible connection to allow fuel to flow from a stationary fuel source into a rapidly rotating hollow shaft. I have found that it is virtually impossible to construct such a fuel connection so as to eliminate the extreme fire hazard attending fuel leaks in jet engines. In accordance with my invention this difiiculty is avoided and fuel may be supplied to the combustion chamber through a stationary fuel pipe or the like which does not require flexible joints as it does not rotate with the engine. This accordingly reduces the fire hazard due to fuel leaks inherent in previous patented devices.

An object of my invention is accordingly to eliminate flexible joints in the fuel supply line and thus avoid fire hazards.

Among the advantages of my improved device over existing jet engines with which I am familiar may be mentioned the following:

(1) No close-tolerance clearances are necessary for the turbine and compressor blades, thereby lowering manufacturing costs and time.

(2) A far stronger bearing structure is possible, making the engine less susceptible to mechanical failures due to metal fatigue.

(3) The design of the engine allows a greater airfiow through the engine than any existing jet engine of a comparable size and weight, giving the engine a greater potential thrust-for-size than other jet engines.

(4) Simplicity of design and construction permits economical manufacture of the engine in sizes small enough to be of use to the hobbyist who builds model airplanes, while at the same time it can be made large enough and strong enough for installations in commercial and military airplanes.

The invention will be more readily understood by reference to the accompanying drawings and the following detailed description in which specific embodiments of my invention are set forth by way of illustration rather than by way of limitation.

In the drawings:

Fig. 1 is a longitudinal section of one form of rotatable engine unit embodying my invention;

Fig. 2 is an end view of the same;

Fig. 3 is a longitudinal section of a modified form in which the engine unit comprises a pair of concentric contra-rotating shells having turbine and compressor blades fixed firmly thereon and revolving with the shells;

Fig. 4 is an end view of the modified construction; and

Fig. 5 is a transverse sectional view thereof.

Referring particularly to the embodiment of my invention shown in Figs. 1 and 2, my improved jet engine comprises an engine unit generally designated by the reference numeral 10, rotatably mounted on front and rear stationary mounting units. The front mounting unit is generally designated by the reference numeral 11 and as shown comprises two sets of arms designed to take thrust and centrifugal loads, such sets of arms being indicated at 12 and 13, respectively, and including four interconnected arms. The engine is also provided with a rear mount comprising a plurality of arms 14 similar to the arms 13 of the front mount, very little thrust load being required to be borne by the rear mount.

The engine unit comprises three interconnected parts, namely an air compressor unit 16 at the forward end of the engine unit, an intermediate tubular body portion 18, and a rear turbine portion 20. As shown the air compressor 16 consists of a number of fan shaped blades 22 rigidly mounted on a large hub 24 which serves as the front bearing for the engine unit as a whole. The compressor blades 22 may be strengthened by the addition of several concentric metal rings 26 which prevent buckling of the fan blades 22. The hub or front bearing 24 is apertured through its center to permit passage therethrough of a fuel inlet pipe 30 connected through a line 31 to any suitable source of fuel. The hub or bearing 24 is securely fastened to the blades 22 of the compressor 16 and the engine unit is rotates as a whole upon the front bearing 24 and the rear bearing or hub 54. The fuel pipe 30 may be provided with a plurality of fuel nozzles 32, the number of which may be varied as desired for proper combustion in a particular instance. For initial ignition of the fuel mixture in the engine a spark plug 34 may be provided. High tension electrical leads 36 may be brought into the combustion chamber either through the central opening in the front hearing, as shown, or if preferred through a central opening in the rear bearing in the event it is undesirable to bring such leads through the front bearing along with the fuel line.

The body 18 of the engine as shown is cylindrical in form and extends between the air compressor 16 at the front of the engine and the turbine 20 at the rear thereof. The body may be and preferably is lined with ceramic material at} in order to enable the engine to withstand operation at very high temperatures.

The rear turbine unit 20 may be similar in construction to the air compressor 16, and as shown comprises a plurality of turbine blades 50 strengthened by concentric rings 52 and mounted securely on the hub 54, which serves as a rear bearing for the engine unit 10. These parts should be made of materials which will withstand high temperatures.

The reference numeral 60 denotes a stationary intermediate bearing which supports the body portion 18 of the engine unit. Any number of bearings may be used along the length of the body portion 18 to prevent warping thereof by reason of the centrifugal force to which the engine is subjected, only one such ring or hearing being shown by way of illustration. All bearings may be of the ball and/ or roller type to minimize friction and heat. Suitable means (not shown) may be provided for lubricating the hearings in a manner which will be apparent to those skilled in the art. Such lubrication is desirable, however, for the successful operation of the engine. Likewise, a fuel pump (not shown) will preferably be employed-for introducing A fuel under pressure through the fuel nozzles 32. All

necessary auxiliary units such as the fuel pump, oil pump 1 bearing 24 of the compressor 16, or on the outer edge blades on members 16 and 26 will be such as to give maximum aerodynamic and thermal etliciency, as will be apparent to those skilled in the art.

The operation'of the engine will be largely apparent from the foregoing description. Air will be'drawn into the engine by rotation of the blades of compressor 16, and fuel is sprayed into the combustion chamber within the body ld'of the engine through the nozzles 32 and is vaporized in the air introduced by means'of the compressor. The fuel-air mixture-will be originally ignited by the spark plug 34 and thereafter combustion will be maintained by the continuous addition of'further air and fuel. turbine 2i to rotate. Since the parts of theengine unit 16, 18 and 2!; are secured together the force applied to the turbine by the outgoing combustion gases will be transmitted to the compressor, causing it to force'more air into the engine, and the operation is continuous so long as fuel is being supplied through the nozzles into'the combustion chamber. The action of the hot gases passing out through the rear of the engine produces a reactionof the engine in the opposite direction, making the engine mechanically useful.

A modified form of my invention is disclosed'in Figs. 3 to 5, inclusive; As in the previously described embodiment the present form of my device. comprises a rotatable engine unit, herein designated by the reference numeral 100, which is freely rotatable about a longitu dinal axis and is provided with a stationary fuel pipe 191 leading from a suitable stationary source of fuel and passing through one end of the rotatable unit ltltl into the interior thereof, the fuel being discharged through suitable nozzles 102 into the'combustion chamber 103 of the engine unit. A suitable spark plug Hi5 may. be provided, as in the previouslyfdescribe'd construction, having high tension electrical leads which may be brought into the combustion chamber through either end of the rotating unit. 7

As in the previously described embodiment, the for ward part of the engine unit 1%, generally designated 167, constitutes the compressor portion of the 'unit,'and the rear portion generally designated 1138 constitutes the turbine portion. The portion 1G9 of the unit intermediate the compressor and turbine portions may be termed the body portion and includes the combustion portion 103. The blades making up the compressor and turbine.

portions of the unit may be of any suitable number and design and are such as to give maximum aerodynamic and thermal efi'iciency. As in the previously described embodiment the compressor and turbine blades are secured to the shell and hub members of the engine and rotate therewith.

.The modified form differs from the previously described embodiment inthat' it consists of two 'or more contra-rotating shells having turbine and compressor The resultant expansion of hot gases forces the 4 direction. The outer shell is shown as provided with end bearings 126 and 122 mounted in stationary front and rear supporting units 12 and 126, respectively. The inner shell 112 is shown as frusto conical in form and is provided with bearings 128, 130 rotatably mounted within the bearings 12% and 122 for the outer shell.

The fuel line 101 and the high tension electrical leads blades fixed firmly thereon and revolving with the shells. The modified form operates on the same general principles as the previously described embodiment, the principal difference being that a second rotating engine unit 1:

similar to the first rotates within the first but in the opposite direction.

As shown the rotatable engine unit 1% comprises an outer shell 11% and an inner. shell 112 concentric with the outer shell and rotating therein but in the opposite supply the spark plug here shown as passingthrough the front bearing 128, though if desired the electrical leads could be passed through the rear bearing .130to avoid close contact with the fuel line. The outer shell 11a is shown as rotatably. supported within stationary rings 14%, 140, suitable bearings being interposed, and

any desired number of rings maybe employed.

The inner shell 112 is shown as frusto conical in form and flaring outwardly from the front toward the rear end of the engine unit. This shell is provided. witha plurality of apertures 142 spaced" throughout substantially the entire area of the wall of the inner combustion cham? her. As in the previously described embodiment the front portion of the rotating engine unit functions as a compressor; and the rear portion as a turbine, the blades of the compressor being suitably shaped and braced as in the previously described embodiment.

Both the-shells ill) and 112 may be lined with heat resistant material, andthe portions'of the engine unit at the rear or discharge end thereof must be made of materials designed to withstand high temperatures. As the inner shell 112 is tapered toward the front, cooler air will then be forced to enter the inner shell throughthe:

holes122, cooling the inner shell by providing a layer of cooler' air next to the surface, helping'keep the heatof the flame away from the combustion chamber walls. This will allow a higher temperature within-the combustion chamber than would be possible otherwise, and it is well known that since a jet engine derives itsenergy from the expansion of heated air the higher temperatures made possible by my design will also make possible a greater thrust for weightand size of the engine.

The invention has been described in detail for-the 'pur-' pose of illustration but itwill be obvious that numerous modifications and variations may be resorted to without departing from the spirit of the invention-.-

1. In a rotary jet engine, the combination ofspa'cedfront and rear stationary supports having axially aligned bearingstherein, front and rear outer hubs-rotatable in the bearings of the respective supports, front and reartinner hubs rotatable in the respective outer hubs, outer compressor blade means and outer turbineblade means rigid with" the respective front and rear" outer hubs and extending radially outwardly therefrom, inner compressor blade means and inner turbine blade means rigid with the'respective front and rear inner hubs and extending radially outwardly therefrom, an open-ended shell having front and rear ends thereof secured to the respective inner compressor blade means and inner turbine blade means coaxially with said bearings and affording an unobstructed combustion chamber therein, an open-ended jacket have path coaxial with-said bearings, and stationary fuel supply means extending into said combustion: chamber through one of said inner hubs.

2. The combination as defined in claim: 11 wherein said shell is ofasfrusto-conical configuration havinga relatively small front end and a relatively large rear end.

3. The combination as defined in claim 1 wherein said shell is of a frusto-conical configuration having a relatively small front end and 'a relatively large rear end, said jacket being of cylindrical form whereby the space between the shell and the jacket is greater in crosssection at the front than at the rear of the engine.

4. The combination as defined in claim 1 wherein said shell is provided with gas passages connecting the space between the shell and said jacket with said corn bustion chamber.

5. The combination as defined in claim 1 wherein said outer compressor blade means and said outer turbine blade means are pitched reversely with respect to the respective inner compressor blade means and the inner turbine blade means, whereby said jacket and said shell are rotated in relatively opposite directions by the flow of gasses through the turbine blade means.

References Cited in the file of this patent UNITED STATES PATENTS 1,960,810 Gordon May 29, 1934 2,360,130 Heppner Oct. 10, 1944 2,410,538 Walton Nov. 5, 1946 2,736,369 Hall Feb. 28, 1956 FOREIGN PATENTS 471,671 Great Britain Sept. 8, 1937 534,801 France Jan. 3, 1922 

